• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.570-577
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• 2000

In this study, using modified tracer method(Constant Rate Injection, CRI method), reaeration rates were measured in the territories of Bokha stream. In case of Kwanri stream, reaeration rates of a diversion were measured simultaneously. Propane gas and Rhodamine-WT were used as gas and dye tracer, respectively. The experimental results show that reaeration rates of the stream were ranged from 6.16 to 24.52 1/day and those of a diversion in Kwanri stream were ranged from 28.39 to 123.61 1/day. It is resulted that mean velocity of stream is a dominant factor in reaeration process and diversion significantly influence on reareation process.

• 한국수자원학회논문집
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• 제34권5호
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• pp.561-566
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• 2001

본 연구는 자연하천에서 유로변경 계획구간에 대한 수리특성을 수치모형시험을 통해 분석하는 것이다. 이 연구를 통해 하천공사 특히 홍수시 피해방지와 하천의 흐름특성을 파악하는 기보자료를 제공할 것이다. 본 연구에서는 수리특성분석을 위해 1차원 모형은 HEC-RAS 모형과 2차원 유한요소모형인 RMA2 모혀이 어떻게 유로만곡부의 흐름형태와 급경사면, 복잡한 하상형태 등의 하천 흐름특성에 영향을 미치는가를 분석하는데, HEC-RAS보다 더 효과적임을 알 수 있었다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.229-234
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• 2011

Feasibility assessment for small hydropower plants using diversion weirs located in stream for agricultural purpose has been studied. The model, which can predict flow duration characteristic of stream, was developed to analyze the inflow caused from rainfall. And another model to predict hydrologic performance for small hydropower plants is established. Preliminary survey was performed identifying several candidate sites, and two sites were selected finally for actual site reconnaissance. During the course of site survey, generating capacity, construction and equipment cost, and payback through life time of each sites were calculated for economical feasibility analysis. The results of this study have estimated that the small hydropower plants using diversion weirs for agricultural purpose may offer better opportunities in future with increasing fuel cost and nation's energy policy.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.68-73
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• 2005

The purpose of this study are to insure flow rate for rural stream in the rural area. The analysis of drying stream characteristics for two streams(Bong-mu, Wang-jang stream) from field survey data. Also, a study area has been determined, and criteria of estimation has been established : criteria such as, available hydrological data, the size of stream lengths and basin areas and regional characteristics. The spacial analysis is applied to stream slopes for upstream and downstream at weirs, stream networks and ground water pump stations, sinuosity of drying stream. As a result of drying streams survey analysis, drying stream characteristics are followed; levee types are earth and natural, cross sectional shapes are trapezoid, stream bed materials are gravels and sands, facilities in streams are weirs. The cause of the reduction analyzed by investigation of the current status of facilities for agricultural water use. Agricultural reservoirs block up the stream and water does not flow over the reservoirs except by storm. They also discharge water through diversion channels and the water diverted does not flow through the natural stream. Farmers directly take water from the stream by weirs.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.752-757
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• 2009

In the last decade, many methods such as greet chamber, reservoir, or debris barrier, have been utilized to manage and prevent muddy water problem. The Vegetative Filter Strip (VFS) has been thought to be one of the most effective methods to trap sediment effectively. The VFS are usually installed at the edge of agricultural areas adjacent to stream or drainage ditches, and it has been shown that the VFS effectively removes pollutants transported with upland runoff. But, if the VFS is installed without any scientific analysis of rainfall-runoff characteristics, soil erosion, and sediment analysis, it may not reduce the sediment as much as expected. Although Soil and Water Assessment Tool (SWAT) model has been used worldwide for many hydrologic and Non-Point Source Pollution (NPSP) analysis at a watershed scale. but it has many limitations in simulating the VFS. Because it considers only 'filter strip width' when the model estimates sediment trapping efficiency, and does not consider the routing of sediment with overland flow option which is expected to maximize the sediment trapping efficiency from upper agricultural subbasin to lower spatially-explicit filter strip. Therefore, the SWAT overland flow option between landuse-subbasins with sediment routing capability was enhanced with modifications in SWAT watershed configuration and SWAT engine. The enhanced SWAT can simulate the sediment trapping efficiency of the VFS in the similar way as the desktop VFSMOD-w system does. Also it now can simulate the effects of overland flow from upper subbasin to reflect the increased runoff volume at the receiving subbasin, which is what is occurring at the field if no diversion channel is installed. In this study, the enhanced SWAT model was applied to small watershed located at Jaun-ri in South Korea to simulate diversion channel and spatially-explicit VFS. It was found that approximately sediment can be reduced by 31%, 65%, 68%, with diversion channel, the VFS, and the VFS with diversion channel, respectively.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.1-8
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• 2008

The paper describes the process and issues encountered during the design and construction of seven kilometres of canal to convey 2.5 cumecs of flow to two power stations. The location of the scheme above the primary reservoir of the Waipori Hydropower scheme in Otago, New Zealand, utilising an existing stream diversion into this reservoir, means that no new water abstraction or diversion consents were required. This mini hydro development associated with the existing Waipori scheme was partly justified by an allocation of carbon credits. The scheme controls are slightly more complicated than many canal and penstock schemes as the canal lengths are considerable in relation to the gradient.

• 한국수자원학회논문집
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• 제41권10호
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• pp.1067-1077
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• 2008

하천유량의 시간적 추세에 대한 이해는 자연환경이나 인간사회를 위한 하천관리 및 수자원계획에 도움을 줄 수 있다. 일반적으로 기온, 강수, 유량 그리고 농업, 홍수방지활동, 저수지 및 유역간의 물이동 등과 같은 하천의 이용은 결과적으로 하천의 흐름에 반영되게 된다. 수자원 시설물 설계에서 받아들여지는 시계열 상에서 수문기상학적 특성이 불변하다는 가정은 기후변화나 하천교란에 의해 더 이상 타당하지 않을 수 있다. 그러므로 수문시계열에서 변화 특성을 검증하고 기술하는 것은 하천관리에 있어 매우 중요한 과제이다. 본 연구에서는 섬진강에서 인위적 유량교란에 의한 유량 변동성 검정을 통계해석에 기반을 둔 단일변수와 집단변수, 그리고 시계열 분석방법으로 구분하여 수행하였다. 검정 결과, 현재 섬진강 수계의 연 유량계열은 동질성을 유지하고 있으나 갈수기 유량계열에서는 변동성이 나타났다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.1-10
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• 2012

Throughout much of the world, many ecological problems have arisen in watersheds where a significant portion of stream flows are diverted to support agriculture production. Within endorheic watersheds (watersheds whose terminus is a terminal lake) these problems are magnified due to the cumulative effect that reduced stream flows have on the condition of the lake at the stream's terminus. Within an endorheic watershed, any diversion of stream flows will cause an imbalance in the terminal lake's water balance, causing the lake to transition to a new equilibrium level that has a smaller volume and surface area. However, the total mass of Total Dissolved Solids within the lake will continue to grow; resulting in a significant increase in the lake's TDS concentration over time. The ecological consequences of increased TDS concentrations can be as limited as the intermittent disruption of productive fisheries, or as drastic as a complete collapse of a lake's ecosystem. A watershed where increasing TDS concentrations have reached critical levels is the Walker Lake watershed, located on the eastern slope of the central Sierra Nevada range in Nevada, USA. The watershed has an area of 10,400 sq. km, with average annual headwater flows and stream flow diversions of 376 million $m^3/yr$ and 370 million $m^3/yr$, respectively. These diversions have resulted in the volume of Walker Lake decreasing from 11.1 billion m3 in 1882 to less than 2.0 billion $m^3$ at the present time. The resulting rise in TDS concentration has been from 2,560 mg/l in 1882 to nearly 15,000 mg/l at the current time. Changes in water management practices over the last century, as well as climate change, have contributed to this problem in varying degrees. These changes include the construction of reservoirs in the 1920s, the pumpage of shallow groundwater for irrigation in the 1960s and the implementation of high efficiency agricultural practices in the 1980s. This paper will examine the impacts that each of these actions, along with changes in the region's climate, has had on stream flow in the Walker River, and ultimately the TDS concentration in Walker Lake.

• 한국수자원학회논문집
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• 제36권6호
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• pp.1069-1082
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• 2003

청도천의 건천화 구간에 내하여 원인을 분석하였다. 분석 방법으로서 이수시설물의 현장조사를 수행하였고, 유량측정 결과와 유역 유출 연속모의 결과를 비교하였다. 여러 건천구간을 쉽게 구분하기 위한 시도로서 위성영상도 이용하였다. 농업용 저수지는 평상시 유출을 차단하고 있다. 그리고 용수로에 물을 공급하여 하천수량을 감소시킨다. 보를 이용한 하천수 취수도 건천화의 원인이다. 특히 까막촌 집수암거는 수백 m의 하천구간을 완전히 마르게 하는 원인이다. 측정된 유량은, 수문순환의 변형이 없는 것으로 가정한 연속모의 결과보다 작았고 이로부터 건천화가 진행되었음을 추측할 수 있었다. 해상도 6.6 m의 KOMPSAT 영상으로 여러 곳의 건천화 의심구간을 실내 작업으로 구분할 수 있었다. 현장답사를 통해 확인한 결과 이들 구간에는 모두 집수암거가 설치되어 있었다. 연구결과는 전원하천의 건천화 원인분석 사례로 참고될 수 있다. 가격이 저렴한 KOMPSAT 영상은 건천화 의심구간 파악을 위한 사전정보로 이용될 수 있다.

• 농업과학연구
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• 제37권2호
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• pp.285-293
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• 2010

To secure instream flow at the Yudeung urban stream reach of Daejeon city in South Korea, Yudeung upstream diversion was designed with total water storage of $59{\times}10^4m^3$, and the upstream Seongol reservoir was planned to raise the bank with various sizes. Downstream streamflows were simulated by considering outflows from upstream diversion and reservoir, and after then flow durations were analyzed and compared with flows of no reservoir condition. In case of no diversion or reservoir upstream, flow durations were $1^{st}$ flow of $84.72m^3/s$, $95^{th}$ flow of $2.10m^3/s$, $185^{th}$ flow of $0.92m^3/s$, $275^{th}$ flow of $0.42m^3/s$, and $355^{th}$ flow of $0.31m^3/s$. In case of upstream diversion, flow durations were $1^{st}$ flow of $94.38m^3/s$, $95^{th}$ flow of $2.96m^3/s$, $185^{th}$ flow of $1.22m^3/s$, $275^{th}$ flow of $0.50m^3/s$, and $355^{th}$ flow of $0.35m^3/s$. The increase flow rates were $0.04m^3/s$ in $355^{th}$ flow, $0.08m^3/s$ in $275^{th}$, and $0.30m^3/s$ in 185th. In case of Seongol reservoir with effective storage capacities of $365{\times}10^4m^3$, $544{\times}10^4m^3$, $750{\times}10^4m^3$, and $992{\times}10^4m^3$, flow durations were $85.5{\sim}83.9m^3/s$ on $1^{st}$ flow, $2.85{\sim}2.57m^3/s$ on $95^{th}$ flow, $1.16{\sim}1.27m^3/s$ on $185^{th}$ flow, $0.64{\sim}0.99m^3/s$ on $275^{th}$ flow, and $0.56{\sim}0.94m^3/s$ on $355^{th}$ flow. The increase flow rates were $0.25{\sim}0.63m^3/s$ in $355^{th}$ flow, $0.22{\sim}0.57m^3/s$ in $275^{th}$, and $0.24{\sim}0.35m^3/s$ in $185^{th}$. The more the sizes of upstream reservoirs increased, the $1^{st}$ and $95^{th}$ flows decreased in which coefficients of determination were 0.92, 0.99, respectively and the $185^{th}$, $275^{th}$, and $355^{th}$ flows increased in which coefficients of determination were 0.93 to 0.99.